1276019-56-7Relevant academic research and scientific papers
A porous metal-organic cage constructed from dirhodium paddle-wheels: Synthesis, structure and catalysis
Chen, Lianfen,Yang, Tao,Cui, Hao,Cai, Tao,Zhang, Li,Su, Cheng-Yong
, p. 20201 - 20209 (2015)
Self-assembly of dirhodium(ii) tetraacetate (Rh2(OAc)4) with a dicarboxylic acid 3,3′-(1,3-phenylenebis(ethyne-2,1-diyl))dibenzoic acid (H2pbeddb) gives rise to a metal-organic cage (MOC) containing Rh-Rh bonds with the formula of [Rh4(pbeddb)4(H2O)2(DMAC)2] (MOC-Rh-1). Single-crystal X-ray diffraction analysis reveals that MOC-Rh-1 shows a lantern-type cage structure, in which a pair of Rh2(CO2)4 paddlewheels is linked by four diacid ligands. The dimensions of the inner cavity of MOC-Rh-1 are 9.5 × 14.8 ?2 (atom-to-atom distances across opposite metal and phenyl groups of pbeddb2-). In the solid phase, the cages are aligned by π-π stacking to form one-dimensional channels (9.5 × 11.1 ?2) through cage windows. Therefore, the crystalline samples of MOC-Rh-1 are porous with the inner and outer cavities of the cages accessible under the heterogeneous condition. MOC-Rh-1 has been fully characterized by EA, TGA, PXRD, IR, UV-vis and XPS measurements. The catalytic tests disclose that activated MOC-Rh-1 is effective in the intramolecular C-H amination of vinyl, dienyl and biaryl azides, leading to the formation of indoles, pyrroles and carbazoles, respectively, and the porous catalyst can be recycled easily and used for at least nine runs without significant loss of activity. In the nine runs, the conversions were in the range of 93-99%, whereas in the tenth run, the conversion was reduced to 78%.
Ligand bridging-angle-driven assembly of molecular architectures based on quadruply bonded Mo-Mo dimers
Li, Jian-Rong,Yakovenko, Andrey A.,Lu, Weigang,Timmons, Daren J.,Zhuang, Wenjuan,Yuan, Daqiang,Zhou, Hong-Cai
supporting information; experimental part, p. 17599 - 17610 (2011/02/26)
A systematic exploration of the assembly of Mo2(O 2C-)4-based metal-organic molecular architectures structurally controlled by the bridging angles of rigid organic linkers has been performed. Twelve bridging dicarboxylate ligands were designed to be of different sizes with bridging angles of 0, 60, 90, and 120° while incorporating a variety of nonbridging functional groups, and these ligands were used as linkers. These dicarboxylate linkers assemble with quadruply bonded Mo-Mo clusters acting as nodes to give 13 molecular architectures, termed metal-organic polygons/polyhedra with metal cluster node arrangements of a linear shape, triangle, octahedron, and cuboctahedron/anti-cuboctahedron. The syntheses of these complexes have been optimized and their structures determined by single-crystal X-ray diffraction. The results have shown that the shape and size of the resulting molecular architecture can be controlled by tuning the bridging angle and size of the linker, respectively. Functionalization of the linker can adjust the solubility of the ensuing molecular assembly but has little or no effect on the geometry of the product. Preliminary gas adsorption, spectroscopic, and electrochemical properties of selected members were also studied. The present work is trying to enrich metal-containing supramolecular chemistry through the inclusion of well-characterized quadruply bonded Mo-Mo units into the structures, which can widen the prospect of additional electronic functionality, thereby leading to novel properties.
